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OB2216
Primary-Side Regulation PWM Power Switch GENERAL DESCRIPTION
OB2216 is an offline PWM Power switch for low power AC/DC charger and adaptor applications. It operates in primary-side sensing and regulation. Consequently, opto-coupler and TL431 could be eliminated. Proprietary Constant Voltage (CV) and Constant Current (CC) control is integrated as shown in the figure below. In CC control, the current and output power setting can be adjusted externally by the sense resistor Rs at CS pin. In CV control, multi-mode operations are utilized to achieve high performance and high efficiency. Device operates in fixed frequency mode at large load conditions, frequency reduction mode at light/medium load and ‘Extended burst mode’ at No/light load conditions. OB2216 offers power on soft start control and protection coverage with auto-recovery features including Cycle-by-Cycle current limiting, VDD clamp and UVLO. Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique together with soft switching control at the totem pole gate drive output.
FEATURES
Primary-side Sensing and Regulation Without TL431 and Opto-coupler Multi-mode Operation for High Efficiency Programmable CV and CC Regulation Adjustable Constant Current and Output Power setting Frequency Shuffling and Adjustable Gate Drive Greatly Improving EMI Power on Soft-start Time (4ms) “Extended Burst Mode Control” for Improved Efficiency and Minimum Standby Design Built-in Leading Edge Blanking (LEB) Cycle-by-Cycle Current Limiting VDD Under Voltage Lockout with Hysteresis (UVLO) VDD Clamp
APPLICATIONS
Low Power AC/DC offline SMPS for Cell Phone Charger Digital Cameras Charger Small Power Adaptor Auxiliary Power for PC, TV etc. Linear Regulator/RCC Replacement OB2216 is offered in DIP8 package
Fig 1. Typical CC/CV Curve
TYPICAL APPLICATION
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OB_DOC_DS_1601
Free Datasheet http://www.datasheet4u.net/
OB2216
Primary-Side Regulation PWM Power Switch GENERAL INFORMATION
Pin Configuration The pin map is shown as below for DIP8. Absolute Maximum Ratings Parameter Drain Voltage (off state) VDD Voltage VDDG Voltage VDD Zener Clamp Continuous Current CS Input Voltage INV Input Voltage Min/Max Operating Junction Temperature TJ Min/Max Storage Temperature Tstg Lead Temperature (Soldering, 10secs) Value -0.3V to Bvdss -0.3 to VDD_clamp -0.3 to VDD_clamp 10 mA -0.3 to 7V -0.3 to 7V -20 to 150 oC -55 to 150 oC 260 oC
Ordering Information Part Number Description OB2216AP DIP8, Pb-free
Note: Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute maximum-rated conditions for extended periods may affect device reliability.
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OB_DOC_DS_1601
Free Datasheet http://www.datasheet4u.net/
OB2216
Primary-Side Regulation PWM Power Switch
Marking Information
TERMINAL ASSIGNMENTS
Pin Num 1 2 3 4 5/6 7/8 Pin Name VDDG VDD INV CS Drain GND I/O P P I I O P Description Internal Gate Driver Power Supply IC DC power supply Input Inverting input of error amplifier (EA). Connected to resistor divider from primary sensing winding reflecting output voltage. PWM duty cycle is determined by EA output and current sense signal at pin 4. Current sense input HV MOSFET Drain Pin. The Drain pin is connected to the primary lead of the transformer Ground
Output Power Table
Product OB2216 230VAC±15% Open Frame1 20W 85-264VAC Open Frame1 15W
Notes:
1. Maximum practical continuous power in an open frame design with sufficient drain pattern as a heat sink, at 50℃ ambient.
©On-Bright Electronics -3-
Confidential
OB_DOC_DS_1601
Free Datasheet http://www.datasheet4u.net/
OB2216
Primary-Side Regulation PWM Power Switch
BLOCK DIAGRAM
VDDG 1 Drain 5/6 Soft Driver Power MOSFET
Frequency Shuffling PWM, & Control Logic CC/CV Operation
Burst mode controller
VDD 2 UVLO
POR
Soft start LEB
CS 4
Regulator
Internal supply
PWM Genterator 1.25V
EA
8 GND Error Amplifier
INV 3
©On-Bright Electronics -4-
Confidential
OB_DOC_DS_1601
Free Datasheet http://www.datasheet4u.net/
OB2216
Primary-Side Regulation PWM Power Switch
ELECTRICAL CHARACTERISTICS
(TA = 25OC, VDD=VDDG=16V, if not otherwise noted) Symbol Parameter Test Conditions Supply Voltage (VDD) Section I DD ST I DD op UVLO(ON) UVLO(OFF) VDD_clamp TLEB Vth_oc Td_oc ZSENSE_IN T_ss CV Section Freq Freq_Burst △f/Freq CC Section Freq Oscillation Frequency Minimum frequency Maximum frequency 1.21 12 50 1.25 50 37.5 1.29 KHz KHz V dB kHz Normal mode frequency Burst Mode Base Frequency Frequency shuffling range 45 50 22 +/-4 55 KHz KHz % Standby Current Operation Current VDD Under Voltage Lockout Enter VDD Under Voltage Lockout Exit IDD=10mA LEB time V th_OC test P.